The present invention relates to a new and improved drafting mechanism for a spinning machine containing a preliminary drafting zone and a main drafting zone.
In its more specific aspects, the drafting mechanism or arrangement of the present development is of the type containing an infeed roller pair comprising an upper infeed roller and a lower infeed roller, an exit or delivery roller pair comprising an upper delivery roller and a lower delivery roller, and an upper apron and a lower apron driven by an apron roller pair. The preliminary drafting zone extends between the infeed roller pair and the nip line formed by the apron rollers pressed against the upper and lower aprons, and the main or primary drafting zone extends between this nip line and the exit roller pair. The lower apron extends beneath the drafting zone and the lower infeed roller.
The present invention is concerned in particular with the cleaning of such drafting mechanisms or arrangements.
From German Published Patent Application No. 2,217,314 a cleaning device is already known to the art in which a cleaner belt is specifically provided for the purpose of cleaning and a friction and deceleration effect is achieved through friction and movement of the cleaner belt on the more rapidly rotating rollers and on the upper apron.
Also, from German Patent No. 908,590 there is known an apron drafting mechanism in which the lower apron extends to a location underneath the infeed cylinder pair. There is no contact of the lower apron with the lower one of these cylinders or rollers.